The invention relates to an automatic fire alarm and extinguisher structure having at least one outlet nozzle or head for discharge of an extinguisher fluid, the supply of which may be controlled by means of a valve, in dependence upon the operating condition of at least one fire alarm.
Known automatic extinguisher systems have the great advantage that upon the presence of the required actuating conditions, they respond immediately to combat the fire. On the other hand, they possess the disadvantage that the extinguishing operation occurs normally at a relatively late time and that frequently the extinguishing fluid, usually water, continues to be discharged until the arrival of the fire department, whereby excess water can cause considerable damage. The first-mentioned disadvantage can be reduced by controlling the extinguisher system by means of an early-warning fire alarm, for example, an ionization smoke alarm.
Controlled extinguisher devices have been known in which, following the response of fire alarms in two different lines, the extinguisher system is triggered. Expensive electro-technical installations are required, as are suitable monitoring devices for the extinguisher fluid valves. However, the extinguishing operation is not terminated once the extinguishing operation is initiated, the extinguishing operation being continued until the arrival of the fire department, or terminated following a predetermined period of time. However, in the latter instance, fire may flare up again after the extinguishing operation, which is not detected and can dangerously develop.
In an effort to overcome the last-mentioned problem, it has heretofore been proposed to constantly monitor the operation of the extinguisher at specific time intervals by means of a flame alarm and to effect discharge of an additional quantity of extinguisher fluid as long as such flame alarm is actuated. However, in such a solution, there remains the problem of installing a line to the central control and to the extinguisher valve means for each fire alarm and to monitor these respective lines.